Sewer-center.



No. 767,111. PATENTED AUG. 9, 1904. w. I]. KELLEY.

SEWER CENTER.

APPLIUATION FILED JAN. 12. 1903.

- N0 MODEL. BBHEBTB-BHEBT 1.

PATENTED AUG. 9, 1904.

W. D. KELLEY. SEWER CENTER.

urmonmn FILED JAN. 12, 1903.

2 SHEETS-SHEET 2.

H0 MODEL.

UNiTEn STATES Patented August 9, 1904.

WILLIAM D. KELLEY, OF YONKERS, NEW YORK.

SEWER-CENTER.

SPECIFICATION forming part of Letters Patent No. 767,111, dated August9, 1904.

Application filed January 12. 1903. Serial No. 138,691. (No model.)

To all whmn it may concern.-

Be it known that 1, WILLIAM D. KELLEY, a citizen of the United States ofAmerica, and a resident of Yonkers, Westchester county, New York, haveinvented certain new and useful Improvements in Sewer-Centers, of whichthe following is a specification.

This invention relates to centers for sewers or tunnels, and moreparticularly to those of small diameter; and its objects generally areto provide a center that is not only readily removable, but which isadjustable, so that the work of constructing a sewer is facilitated andthe structure rendered more perfect Usually in constructing sewersbricklayers work too close to the line or hug the line too closely, thuscausing a lip or break in the joint on both sides of the spring-linewhere the centers join the invert. To overcome this requires removal andplaning down of the sewercenters. This is avoided by the presentinvention, in which the arched brickwork is enabled to be built rapidlyand exactly flush with the invert brickwork and a smooth connection orjoint to be made whether the invert brickwork be larger or smaller thanthe theoretical invert. Although the ribs for false work of sewers ortunnels have hereto fore been made up of hinged sections in part, theribs are, so far as I am aware, complete closed curves, to remove whichit is absolutely necessary that a workman enter the sewer, which isoften full of debris and interferes with the removal of the ribs. If thesewer be, say, two feet and six inches in diameter, this is all the morethe case, and particularly where solid stiff ribs are used, ascustomary, which ribs require that the workman crawl through the sewerand lying on his back chop out the wooden center. An important object ofmy invention is avoid this breaking up and complete destruction ofcenters and the necessity of one entering the sewer, involved as it iswith considerable danger, it only being required for removing thecenters that the blocking which supports the centers be knocked out by apole, whereupon the arched false work immediately collapses. drops down,and is easily removed.

A further object of my invention is to en able the center to remain inthe sewer during the process of construction for a week or a month, ifdesired, as the consequent swelling of the wood or the setting of thecement, which adheres to the lagging, does not preclude their easy andsafe removal.

A. still further object of my invention is to gain the enumeratedadvantages and at the same time leave the entire bottom of the sewerunobstructed for the ready flow of water, so that the sewer as fast ascompleted may be made use of for receiving thetrencl1-water which may bepumped into it.

Still further objects are to reduce both the cost of making and the costof putting in sewer false work to a minimum and to simplify themanufacture of sewer-centers possessing the advantages enumerated.

l/Vith these objects in view my invention resides in an arched centerfor sewers and tunnels consisting of certain details of construction andcombinations of parts to be hereinafter described and then claimed.

In the accompanying drawings, Figure 1 is a perspective view of thepreferred form of my improved sewer-center opened for use, three beingshown, for example, connected by suitable lagging. Fig. 2 is aperspective View of the same collapsed. Fig. 3 is a cross-section of aninvert of a sewer or tunnel, showing my sewer-center in position toreceive the arch. Fig. 4 is a cross-section of a sewer, showing mysewer-center in use after building the arch. Fig. 5 is a similar sectionshow ing the blocking removed and the center down ready for removal; andFig. 6 is a sectional view of a sewer, showing a modified form ofcenter.

The sewer-center shown is a unitary structure consisting of arcuate orsegmental members A B, preferably hinged together at the inner cornersof the adjacent ends of the members by a hinge C, which permits themembers to fold and their inner faces to close upon each other. Ineffect, this manner of joining the folded members forms a gore D betweentheir adjacent ends, which increases or decreases in width according tothe increase or decrease in the span of the outer extremities of themembers. The gore allows the members to extend to a greater diameterthan that of the sewer, so as to be adjustable at the spring-line of thearch. Specifically each member of the preferred form of the inventionforms a leg to the sewer-center, which thus consists of two legs hingedtogether. From the modification shown in Fig. 6 it is clear that theremay be a number of hinged members a greater than two. The members of thesewer-center are made, preferably at a sawmilLof wood in quantities andhinged properly, there being no carpenter-work or the like required atthe field of operation of sewer construction.

It is evident that the invention is not limited to the form ofhinge-joint, as various forms of hinges joining or pivoting the membersof the sewer-center will readily suggest themselves to those skilled inthe art. Neither is the invention restricted to the formation of gaps ina perfect semicircle; but by forming them in that way the center may bespread, as well as drawn in or collapsed. The outer edges of thesections are preferably, but not necessarily, formed as segments of acircle.

Given now, say, a set of twelve of the folding sewer-centers, thebricklayer may start to work on a sewer of average length. The invert islaid, and then when the spring-line is reached a beam E, of any suitablematerial at hand, is placed in position, as shown, a couple of blocks F,of wood, or two bricks laid upon each end of the beam, and thesewer-center then supported by the lower ends of the legs or membersthereof resting upon the blocks. The brick-mason is now enabled, due tothe gore formed at the adjacent ends of the members A B and the smallwedge G inserted in it,'to enlarge or decrease the diameter of thecenter or false work at will without loss of time, the planing down ofthe center, or injury thereto, thus allowing 'a smooth perfect joint tobe made at the spring- Having adjusted the center, the Work of buildingup the arch of the sewer or tunnel is proceeded with. The lagging isnailed to the centers, as usual, before the ribs are set in place,except the two top strips it, which are preferably left loose, so thatthe opening formed can be used as ahand-hole for adjusting the interiorribs. The arch having been completed and the cement set, the centers maybe removed, this being done either by going into the sewer, if ofsufficient diameter and practically free of debris, or, if the sewer beof small diameter-say two feet six inches by taking a pole and pushingout the blocks and beam from under the centers, allowing the two halves,legs, or members of the centers to be folded together or collapsed intoa smaller space.

By my improved construction of sewer-center and the manner of supportingthe same the entire bottom of the sewer-tunnel is left unobstructed forthe flow of water.

All parts of the device described are combined in one unitary stuctureand cannot be lost or separated from each other, and they can be storedalways in a small compass.

Having thus described my invention, what I claim as new therein, anddesire to secure by Letters Patent, is

A sewer-center, consisting of a unitary semicircular rib formed ofhinged members, and having gores or gaps between the ends of themembers, substantially as described.

Signed at Yonkers, New York, this 30th day of December, 1902.

WILLIAM D. KELLEY.

Witnesses:

JAMEs K. CUDDY, SAM M. HITCHOOOK.

